Learner out of bed with popular plant (5)
I believe the answer is:
lupin
'plant' is the definition.
The answer is an example.
'learner out of bed with popular' is the wordplay.
'learner' becomes 'l' (as in a learner driver with L-plates on their car).
'out of bed' becomes 'up' (synonyms).
'with' is a charade indicator (letters next to each other).
'popular' becomes 'in' (something that's 'in' is fashionable).
'l'+'up'+'in'='LUPIN'
(Other definitions for lupin that I've seen before include "9 [BLOOM]" , "Flower called after wolf" , "Plant with erect spikes of usually purplish-blue flowers" , "Fodder plant" , "Spiky flower" .)